A clinical trial compared percutaneous transluminal coronary angioplasty (PTCA) with medical therapy in treating single-vessel coronary-artery disease [13]. Researchers randomly assigned 107 patients to medical therapy and 105 to PTCA. Patients were given exercise tests at baseline and after 6 months of follow-up. Exercise tests were performed up to maximal effort until clinical signs (such as angina) were present. The results shown in Table 8.21 were obtained for change in total duration of exercise (min) (6 months – baseline).
Table 8.21 Change in total duration of exercise for patients with coronary-artery disease randomized to medical therapy vs. PTCA
Perform the test in Problem 8.66 for the medical therapy group, and report a p-value.
8.66 What test can be performed to test for change in mean total duration of exercise for a specific treatment group?
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